Firing device

ABSTRACT

The invention relates to a so-called fuze damping in projectiles, in particular with a built-in firing delay. 
     The invention proposes a projectile ( 1 ) having a rear part ( 1   a ) and a fuze ( 2 ) , wherein at least one damping element ( 7 ) is inserted between a fuze base ( 5 ) and the projectile ( 1 ) and/or between a fuze shoulder ( 6 ) and a possible threaded ring ( 4 ) or similar attachment element. The damping element ( 7 ) is in the form of a disc, ring or pot, and is composed of a material with a lower acoustic impedance than the material of the projectile ( 1 ).

The invention relates to a so-called fuze damping in projectiles, in particular with a built-in firing delay.

In projectiles having a firing device, whose fuze is intended to still be functional during or after the penetration of targets, the problem arises that the oscillations of the projectile initiated by the impact shock can have a negative influence on or even destroy the sensitive components of the firing device. The oscillations which are transmitted to the firing device are caused on the one hand by the sudden deceleration of the projectile and on the other hand by shock waves or sound waves which are introduced into the projectile.

In previous practice, the fuze components were therefore hardened and/or encapsulated in order in this way to reduce the introduction of oscillations to the firing system. However, in the case of extreme target structures, measures such as these are not sufficient, and the functional reliability of the firing system cannot always be guaranteed, since they are not sufficient to compensate for the oscillations (for example on building targets) which occur in or on the fuze on penetration.

The purpose of the invention is therefore to include a device in the projectile which minimizes the introduction of oscillations into the firing device and nevertheless guarantees the functional reliability of the fuze itself.

The object is achieved by the features of patent Claim 1. Dependent claims specify the preferred embodiments.

The invention is based on the idea of including in the projectile a damping system or a damping device, comprising damping and decoupling elements, in order in this way to dissipate oscillations from the firing device.

Damping devices in projectiles are known per se.

For example, DE 698 14 022 T2 (EP 0 928 948 B1) describes a projectile having multiple charges and having a damping section which is compressed in the longitudinal direction when the projectile is subjected to the launch acceleration. A gap between the damping section and a rigid support apparatus disappears, as a result of which the support apparatus comes into direct contact with the contact surfaces.

DE 60 2004 001 496 T2 relates to an anti-bunker munition, in which a submunition and the apparatus for ejection of the submunition are isolated from at least one of the walls of the internal cavity by means of a damping material.

In contrast, this solution provides damping and mechanical decoupling of the firing device, which is included in a fixed manner in the projectile, as a result of which peaks on impact are dissipated and can no longer have a destructive effect on the mechanical and electronic components. The additionally included damping device therefore reduces the effects of the projectile oscillations by means of additional materials of low density and with high damping characteristics in both sound waves and shock waves. The damping device in this case decouples the firing device from the mostly metallic structural area in the projectile.

The oscillations are preferably dissipated by a plastic, which is favoured as the damping and decoupling material. The load on all the components of the fuze, of the firing device and of the firing chain is thus reduced, thus ensuring operation even against extreme targets. The fuze function—delayed fuzing after penetration of the target=delay−function—is now also possible, guaranteeing the functional reliability of this function.

The materials are preferably determined with the assistance of computer simulations (for example ABACUS EXPLICIT from the Simulia Company). Different penetration processes of a projectile on passing through steel plates/armour plates/brick walls/concrete walls and sand bunkers etc. are simulated in the simulation computer, with the load spectrum for the projectile/system being determined in this case, on the basis of which the material and the geometry of the fuze damping are designed. Alternatively, however, it is also possible to use empirical values.

In one preferred embodiment, discs are inserted in front of and behind the fuze or the firing device and these discs are screwed to the firing system with an appropriate torque. A material is selected for the discs such that the optimum damping for the firing system is achieved for all targets with the selected (defined) torque.

The thickness of the discs is in this case matched to the load spectra (for example by simulation), thus allowing optimization of the damping system, in particular for specific targets.

Since the damping system is composed mainly of a small number of discs, preferably of plastic, the solution is also highly cost effective. Existing firing systems can be modified without major effort.

Virtually complete packaging of the fuze with the material that absorbs the damping is also possible and technically feasible.

The invention will be explained in more detail using one exemplary embodiment and with reference to the drawing. In the drawing, the single FIGURE shows a projectile 1 with a rear part 1 a in which a firing system is located comprising a fuze 2 and a firing booster 3 (if provided in the design). The firing system is held in the projectile 1 by, for example, a threaded ring 4 or an attachment element of some similar type.

At least one damping element 7 is inserted between a fuze base 5 and the projectile 1 and/or between a fuze shoulder 6 and the threaded ring 4. The damping element 7, which is in the form of a disc or ring (or else is U-shaped) is preferably composed of plastic (for example polyethylene =PE) or of a material with a lower acoustic impedance than the material of the projectile 1. The threaded ring 4 is preferably tightened with a defined torque. In consequence, the damping surfaces of the damping material 7 rest completely on the firing system and no gaps are created. At the same time, it is used to fix the firing system and for its attachment in the projectile 1.

The arrow indicates the firing direction. When the projectile 1 strikes a target, which is not illustrated in any more detail, the resultant oscillations are absorbed by the damping element or elements 7. The projectile 7 is itself fired with a firing delay, only after the projectile 1 has penetrated through the target, with the residual forces being sufficient to initiate the fuze. 

1. Projectile having a rear part and a fuze, wherein at least one damping element is inserted between a fuze base and the projectile and/or between a fuze shoulder and a possible threaded ring or similar attachment element.
 2. Projectile according to claim 1, characterized in that the damping element is in a form selected from the group consistent of a disc, ring or pot.
 3. Projectile according to claim 1, characterized in that the damping element comprises a material with a lower acoustic impedance than the material of the projectile.
 4. Projectile according to claim 2, characterized in that the damping element comprises a material with a lower acoustic impedance than the material of the projectile.
 5. Projectile according to claim 3, characterized in that the damping element comprises a plastic.
 6. Projectile according to claim 5, characterized in that the plastic is PE. 